Thinking critically with psychological Science

1. Thinking critically with psychological Science Chapter one

2. The Need for Psychological Science • We as humans can’t solely rely on our intuition and common sense • Three phenomena illustrate this: • Hindsight bias • Judgmental overconfidence • Tendency to perceive patterns in random events

3. The Need for Psychological Science • Hindsight bias • Tendency to believe, after learning an outcome, that we could have predicted it. • Also known as the I-knew-it-all-along phenomenon. HINDSIGHT BIAS When drilling the Deepwater Horizon oil well in 2010, oil industry employees took some shortcuts and ignored some warning signs, without intending to harm the environment or their companies’ reputations. After the resulting Gulf oil spill, with the benefit of 20/20 hindsight, the foolishness of those judgments became obvious.

4. The Need for Psychological Science • Overconfidence • People tend to think they know more than they do. • This occurs in academic and social behavior. WREAT → WATER ETRYN → ENTRY GRABE → BARGE • How long would it take you to unscramble these anagrams?

5. The Need for Psychological Science • We as people tend perceive patterns to make sense the world around them. • Even in random, unrelated data people often find order • random sequences often do not look random. • People trust their intuition more than they should because intuitive thinking is flawed. During the 2010 World Cup, a German octopus—Paul, “the oracle of Oberhausen”—selected the right box and correctly predicted the outcomes of Germany’s matches with Spain.

6. The Need for Psychological Science • Why do we tend to rely to much on our intuition and make errors? • How can we determine if it is reality or an illusion? • Scientific inquiry can aid us in determining reality from illusion

7. The Scientific Attitude • Thinking critically • Critical thinking refers forming and evaluating knowledge than simply using intuition. • helps develop more effective and accurate ways to figure out what makes people do, think, and feel the things they do.

8. The Scientific Attitude The Scientific Attitude is made up of three main components • Curiosity • Skepticism • Humility

9. The Scientific Attitude • Curiosity • Includes a passion to explore and understand the world • With the tendency to want to do this without misleading or being misled

10. The Scientific Attitude • Skepticism • Supports questions about behavior and mental processes: What do you mean? How do you know? • If you are skeptical you don’t blindly accept facts

11. Humility • Involves awareness that mistakes are possible and willingness to be surprised • It also involves the ability to accept when you are wrong

12. The Scientific Method • Psychologists, like all scientists, use the scientific method to construct theories that organize, summarize and simplify observations.

13. The Scientific Method • Theory • isan explanation that integrates principles and organizes and predicts behavior or events. An example of a theory • low self-esteem contributes to depression.

14. The Scientific Method • Hypothesis • is a testable prediction, often prompted by a theory, to enable us to accept, reject or revise the theory. An example of a hypothesis People with low self-esteem are apt to feel more depressed.

15. The Scientific Method • Operational definition • Carefully worded statement of the exact procedures (operations) used in a research study Operational Definition example Self-esteem is the judgement of oneself as well as an attitude toward oneself

16. The Scientific Method • Replication • Repeating a research study to see whether the basic finding extends to other participants and circumstances • usually with different participants in different situations

17. Research • Descriptive research is a systematic, objective observation of people • The goal is to provide a clear, accurate picture of people’s behaviors, thoughts, and attributes • Cross-sectional and longitudinal studies are often used Cross-sectional is cost effective and results are immediate, but may not be accurate . Longitudinal is more expensive and results take years, but tend do be accurate.

18. Research • Random Sampling • If each member of a population has an equal chance of inclusion into a sample, it is called a random sample (unbiased). • If the survey sample is biased, its results are not valid

19. Descriptive Research • Case Study • Examines one individual in depth • Provides fruitful ideas • Cannot be used to generalize

20. Descriptive Research • Naturalistic Observation • Records behavior in natural environment • Describes but does not explain behavior • Can be revealing

21. Descriptive Research • Surveys and Interviews • Examines many cases in less depth • Wording effect • Random sampling • Utilizes random sampling of population for best results

22. Research - Correlation • A Correlation is an observation that two traits or attributes are related to each other (thus, they are “co”-related) • Looks at the “relationship” between two variables • Correlation does NOT show causation

23. Research Correlation The range is from 0 – 1 The closer the score to 1 the stronger the relationship The once can be +1 or -1 (the +/- indicate the direction of the scatterplot slope

24. Research Correlation • Illusory correlation • Refers to the perception of a relationship between two variables when only a minor or no relationship actually exists • May be fed by regression toward the mean • Refers to the tendency for extreme or unusual scores or events to fall back (regress) toward the average

25. Correlation does not show causation!!!!! ONLY an EXPERIMENT can!!! As you can see there is a relationship between these variables, but no way to show causation

26. Research Experimentation • With experiments, researchers can focus on the possible effects of one or more factors (variables) in several ways. • Manipulating the factors of interest (independent variable aka IV) to determine their effects (dependent variable aka DV) • Controlling variables by assigning them to a control or experimental group • Experimental group = gets the IV (item of interest in the study) • control group = gets the placebo (fake)

27. Research Experimentation • Random Assignment • Assigning participants to experimental ( IV) and control (placebo/original condition) conditions by random assignment minimizes pre-existing differences between the two groups. Looking at the effect of breast milk on intelligence

28. Research Experimentation • Double-blind procedure: Eliminating bias • Neither those in the study nor those collecting the data know which group is receiving the treatment. • Treatment’s actual effects can be separated from potential placebo effect. • Placebo effect • Effect involves results caused by expectations alone.

29. Research Experimentation • Independent variable (IV) • that is manipulated; the variable whose effect is being studied • Dependent variable (DV) • Factor that is measured; the variable that may change when the independent variable is manipulated

30. Research Experimentation • Confounding variable in an experiment • Factor other than the independent variable that might produce an effect

31. Research Experimentation • Experiment purpose • Test theoretical principles, • Does not recreate exact everyday life behaviors • Resulting principles • Can help explain everyday behavior • Psychological science • Focuses on seeking general principles that help explain many behaviors and less on particular behavior

33. Can experiments illuminate everyday life? • Yes, to some extent • Controlled experiments are artificial environments are created in laboratory experiments to test general theoretical principles. • These general principles help explain everyday behaviors.

34. Ethics Professional associations and funding agency guidelines • Universities: IRB ethics committees; laboratory regulation and inspection • British Psychological Society (BPS): Guidelines for reasonably natural living conditions and companions for social animals • American Psychological Association (APA): Guidelines for humane treatment and minimization of infection, illness, and pain • European Parliament: Standards for animal care and housing

35. Ethics Is it ethical to experiment on animals? • Yes. To gain insights to devastating and fatal diseases. All researchers who deal with animal research are required to follow ethical guidelines in caring for these animals. Is it ethical to experiment on people? • Yes. Experiments that do not involve any kind of physical or psychological harm beyond normal levels encountered in daily life may be carried out.

36. Ethics • Ethics codes of APA, Britain’s BPS, and university ethics committee • Obtain potential participants’ informed consent before the experiment • Protect them from harm and discomfort • Keep information about individual participants confidential • Fully debrief people (explain the research afterward)

37. Statistics in Psychology

38. Statistics in Psychology • Measures of Central Tendency • Mode: Most frequently occurring score(s) in a distribution • Mean: Arithmetic average of a distribution, obtained by adding the scores and then dividing by the number of scores; can be distorted by few atypical scores • Median: Middle score in a distribution; half the scores are above it and half are below it.

39. Statistics in Psychology A skewed distribution This graphic representation of the distribution of a village’s income illustrates the three measures of central tendency—mode, median, and mean. Note how just a few high incomes make the mean—the fulcrum point that balances the incomes above and below—deceptively high.

40. Statistics in Psychology • Measures of variation • Range: Difference between the highest and lowest scores in a distribution • To calculate the range subtract the lowest number from the highest number

41. Statistics in Psychology • Standard deviation: Computed measure of how much scores vary around the mean score. • A standard deviation of 5 or more is considered significant in psychology

42. Statistics in Psychology • Normal curve (normal distribution): Symmetrical, bell-shaped curve that describes the distribution of many types of data; most scores fall near the mean (about 68 percent fall within one standard deviation of it) and fewer and fewer near the extremes

43. Statistics in Psychology • When is an observed difference reliable? • Representative samples are better than biased samples. • Less-variable observations are more reliable than those that are more variable. • More cases are better than fewer.

44. Statistics in Psychology • When is an observed difference significant? • When sample averages are reliable and difference between them is relatively large the difference statistically significant. • Observed difference is probably not due to chance variation between the samples. • In psychological research, proof beyond a reasonable doubt means that the odds of its occurrence by chance are less than 5 percent.